In general, an alternator is in the form of a structure made up of two metal bearing assemblies or half-shells, with each half-shell receiving one end of a rotor shaft, and with a stator being mounted stationary relative to the half-shells.
Such an alternator also includes a regulator circuit and a set of diodes for rectifying the alternating voltages delivered by the stator windings.
These diodes are generally mounted by means of appropriate fittings on the outside of one of the alternator half-shells, i.e. the "back" half-shell as compared with the front half-shell which is situated adjacent to the pulley wheel for driving the alternator.
A requirement when designing an alternator is to ensure that the arrangement, in particular of the rectifier diodes, does not excessively increase the axial length of the alternator.
To reduce this length, in the context of a polyphase alternator having one set of diodes at the negative side and another set of diodes at the positive side, whose bodies are connected respectively to ground and to the positive output terminal of the alternator, it is known that the negative side diodes can be engaged as force-fits directly in the back half-shell of the alternator.
However, the positive side diodes must be situated some distance axially from the negative side diodes, and appropriate means for connecting the diodes to the windings of the alternator stator must also be housed in the vicinity of the diodes.